Introduction: Diabetes is a multifactorial syndrome with high prevalence which may induce serious disorders in the body organs like the liver and kidney. This study aimed to compare the effects of the alcoholic extract of the aerial parts of Swertia longifolia Boiss on blood glucose, lipid profiles and liver and kidney function tests in streptozotocin-induced diabetes. Methods: Thirty five male rats were put into five groups: control, diabetic control and three diabetic experimental groups which were gavaged with alcoholic extract of Swertia longifolia Boiss at doses of 100 and 200 mg/kg BW and glibenclamide at a dose of 10 mg/kg BW, respectively. Diabetes was induced by intraperitoneal injection of streptozotocin. At the end of day 21 blood samples were collected from all groups and the blood factors were measured and analyzed. Results: The levels of creatinine, urea, liver enzymes, cholesterol and low density lipoprotein increased in the diabetic control group compared to the control, while the mentioned factors in the groups receiving Swertia longifolia Boiss alcoholic extract decreased significantly (P<0.05). In the experimental group receiving glibenclamide, the levels of creatinine, urea and lipid profiles also decreased, while the levels of liver enzymes and insulin significantly increased (P<0.05). Conclusion: The consumption of the alcoholic extract of the aerial parts of Swertia longifolia Boiss by lowering lipid profiles, liver enzymes, creatinine and urea as well as increasing insulin levels had beneficial effects on the hepatic and renal functions and could alleviate the symptoms of increased glucose and hyperlipidemia in diabetic rats.